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The study of magnetically arrested disks (MAD) has attracted strong interest in recent years because these disk configurations were found to generate strong jets, as observed in many accreting systems. Here, we present the results of 14 general relativistic magnetohydrodynamic simulations of advection-dominated accretion flow in the MAD state across black hole (BH) spins, carried out with cuHARM. Our main findings are as follows. (i) The jets transport a significant amount of angular momentum to infinity in the form of Maxwell stresses. For positive, high spin, the rate of angular momentum transport is about five times higher than for negative spin. This contribution is nearly absent for a nonrotating BH. (ii) The mass accretion rate and the MAD parameter, both calculated at the horizon, are not correlated. However, their time derivatives are anticorrelated for every spin. (iii) For zero spin, the contribution of the toroidal component of the magnetic field to the magnetic pressure is negligible, while for a fast-spinning BH, it is on the same order as the contribution of the radial magnetic component. For high positive spin, the toroidal component even dominates. (iv) For negative spins, the jets are narrower than their positive-spin counterparts, while their fluctuations are stronger. The weak jet from the nonrotating BH is the widest with the weakest fluctuations. Our results highlight the complex nonlinear connection between the black hole spin and the resulting disk and jet properties in the MAD regime.

We introduce a new GPU-accelerated general relativistic magnetohydrodynamic code based on HARM, which we call cuHARM. The code is written in CUDA-C and uses OpenMP to parallelize multi-GPU setups. Our code allows us to run high-resolution simulations of accretion disks and the formation and structure of jets without a need for multinode supercomputer infrastructure. A 256 ^3 simulation is well within the reach of an Nvidia DGX-V100 server, with the computation being about 10 times faster than if only the CPU is used. We use this code to examine several disk structures all in the SANE state. We find that (i) increasing the magnetic field in the SANE state does not affect the mass accretion rate; (ii) simultaneously increasing the disk size and the magnetic field, while keeping the ratio of energies fixed, leads to the destruction of the jet once the magnetic flux through the horizon decreases below a certain limit (this demonstrates that the existence of a jet is a function of the initial mass distribution, and not of the initial intensity of the magnetic field, since the magnetorotational instability dictates the evolution of the magnetic field); and (iii) the structure of the jet is a weak function of the adiabatic index of the gas, with relativistic gas tending to have a wider jet.

Fast radio bursts (FRBs) are bright millisecond or shorter duration transient events. Here, the authors propose that FRB 20201124A comes from a binary system of a magnetar and a Be star with a decretion disk.

Abstract We report on a search for double beta decay of $$^{130}\hbox {Te}$$ 130Te to the first $$0^{+}$$ 0+ excited state of $$^{130}\hbox {Xe}$$ 130Xe using a $$9.8\,\hbox {kg}\cdot \hbox {yr}$$ 9.8kg·yr exposure of $$^{130}\hbox {Te}$$ 130Te collected with the CUORE-0 experiment. In this work we exploit different topologies of coincident events to search for both the neutrinoless and two-neutrino double beta decay modes. We find no evidence for either mode and place lower bounds on the half-lives: $$T^{0\nu }_{0^+_1}>7.9\cdot 10^{23}\hbox {yr}$$ T01+0ν>7.9·1023yr and $$T^{2\nu }_{0^+_1}>2.4\cdot 10^{23}\hbox {yr}$$ T01+2ν>2.4·1023yr ($$90\%\,\hbox {CL}$$ 90%CL ). Combining our results with those obtained by the CUORICINO experiment, we achieve the most stringent constraints available for these processes: $$T^{0\nu }_{0^+_1}>1.4\cdot 10^{24}\hbox {yr}$$ T01+0ν>1.4·1024yr and $$T^{2\nu }_{0^+_1}>2.5\cdot 10^{23}\hbox {yr}$$ T01+2ν>2.5·1023yr ($$90\%\,\hbox {CL}$$ 90%CL ).

The weak-signal detection technologies based on stochastic resonance (SR) play important roles in the vibration-based health monitoring and fault diagnosis of rolling bearings, especially at their early-fault stage. Aiming at the parameter-fixed vibration signals in practical engineering, it is feasible to diagnose the potential rolling bearing faults through adaptively adjusting the SR system parameters, as well as other generalized parameters such as the amplitude-transformation coefficient and scale-transformation coefficient. However, extant adaptive adjustment methods focus on the system parameters, while the adjustments of other adjustable parameters have not been fully studied, thus limiting the detection performance of the adaptive SR method. In order to further enhance the detection performance of adaptive SR methods and extend their application in rolling bearing fault diagnosis, an adaptive multiparameter-adjusting SR (AMPASR) method for bistable systems based on particle swarm optimization (PSO) algorithm is proposed in this paper. This method can produce optimal SR output through adaptively adjusting multiparameters, thus realizing fault feature extraction and further fault diagnosis. Furthermore, the influence of algorithm parameters on the optimization results is discussed, and the optimization results of the Langevin system and the Duffing system are compared. Finally, we propose a weak-signal detection method based on the AMPASR of the Duffing system and employ three diagnosis examples involving inner ring fault, outer ring fault, and rolling element fault diagnoses to demonstrate its feasibility in rolling bearing fault diagnosis.

Abstract CUORE is a tonne-scale cryogenic detector operating at the Laboratori Nazionali del Gran Sasso (LNGS) that uses tellurium dioxide bolometers to search for neutrinoless double-beta decay of $$^{130}$$ 130 Te. CUORE is also suitable to search for low energy rare events such as solar axions or WIMP scattering, thanks to its ultra-low background and large target mass. However, to conduct such sensitive searches requires improving the energy threshold to 10 keV. In this paper, we describe the analysis techniques developed for the low energy analysis of CUORE-like detectors, using the data acquired from November 2013 to March 2015 by CUORE-0, a single-tower prototype designed to validate the assembly procedure and new cleaning techniques of CUORE. We explain the energy threshold optimization, continuous monitoring of the trigger efficiency, data and event selection, and energy calibration at low energies in detail. We also present the low energy background spectrum of CUORE-0 below $$60 \, \mathrm {keV}$$ 60 keV . Finally, we report the sensitivity of CUORE to WIMP annual modulation using the CUORE-0 energy threshold and background, as well as an estimate of the uncertainty on the nuclear quenching factor from nuclear recoils inCUORE-0.

Abstract The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of $$^{130}$$ 130 Te with an array of 988 TeO $$_2$$ 2 bolometers operating at temperatures around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity on the $$^{130}$$ 130 Te decay half-life of 9 $$\times $$ × 10 $$^{25}$$ 25 years after 5 years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10 $$^{-2}$$ - 2 counts/keV/kg/year. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of $$^{130}$$ 130 Te is expected.

Abstract We report a study of the CUORE sensitivity to neutrinoless double beta ( $$0\nu \beta \beta $$ 0 ν β β ) decay. We used a Bayesian analysis based on a toy Monte Carlo (MC) approach to extract the exclusion sensitivity to the $$0\nu \beta \beta $$ 0 ν β β decay half-life ( $$T_{1/2}^{\,0\nu }$$ T 1 / 2 0 ν ) at $$90\%$$ 90 % credibility interval (CI) – i.e. the interval containing the true value of $$T_{1/2}^{\,0\nu }$$ T 1 / 2 0 ν with $$90\%$$ 90 % probability – and the $$3~\sigma $$ 3 σ discovery sensitivity. We consider various background levels and energy resolutions, and describe the influence of the data division in subsets with different background levels. If the background level and the energy resolution meet the expectation, CUORE will reach a $$90\%$$ 90 % CI exclusion sensitivity of $$2\cdot 10^{25}$$ 2 · 10 25 year with 3 months, and $$9\cdot 10^{25}$$ 9 · 10 25 year with 5 years of live time. Under the same conditions, the discovery sensitivity after 3 months and 5 years will be $$7\cdot 10^{24}$$ 7 · 10 24 year and $$4\cdot 10^{25}$$ 4 · 10 25 year, respectively.

MnBi magnets with a high content of low temperature phase (LTP) and excellent magnetic properties were prepared by spark plasma sintering (SPS) using ball milling powders as precursors without magnetic purification. A complicated intergranular phase, which contains Mn phase, Bi phase, MnO phase, and even amorphous phase in MnBi magnets, was characterized and reported systematically. It was found that the formation of intergranular phase which was contributed by ball milling precursors and sintering mechanism, jointly, had important influence on the magnetic properties. The appropriate content of intergranular phase was beneficial in improving the coercivity due to the strong magnetic isolation effects. The optimum magnetic properties with Mr=26.0 emu/g, Hci= 7.11 kOe and (BH)max=1.53 MGOe at room temperature, and a maximum value Hci= 25.37 kOe at 550 K can be obtained. Strongly favorable magnetic properties make SPSed MnBi magnets an attractive candidate material for small permanent magnets used in high-temperature applications.

Purpose. Our study analyses clinical trials and evaluates the efficacy of adding cetuximab in systematic chemotherapy for unresectable colorectal cancer liver-confined metastases patients. Materials and Methods. Search EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials for RCTs comparing chemotherapy plus cetuximab with chemotherapy alone for KRAS wild type patients with colorectal cancer liver metastases (CRLMs). We calculated the relative risks (RRs) with 95% confidence interval and performed meta-analysis of hazard ratios (HRs) for the R0 resection rate, the overall response rate (ORR), the progression-free survival (PFS) and overall survival (OS). Results. 1173 articles were retrieved and 4 RCTs were available for our study. The four studies involved 504 KRAS wild type patients with CRLMs. The addition of cetuximab significantly improved all the 4 outcomes: the R0 resection rate (RR 2.03, p=0.004), the ORR (RR 1.76, p